EPA to Begin Checking Water for Deadly Germ

In a move that environmentalists and water utilities said is a major step toward attacking a deadly form of drinking water pollution, the Environmental Protection Agency said Thursday that it will begin to monitor large municipal water supplies for the microbe cryptosporidium.

The goal of the 18-month project is to establish the nation’s first drinking water standards for an organism that was responsible for 39 deaths during an outbreak in Las Vegas in 1994, about 100 deaths in Milwaukee in 1993 and about 400,000 cases there of often severe diarrhea and vomiting.

“It is the most important contaminant in drinking water today,” said Joan Rose, a professor of water microbiology at the University of South Florida in Tampa.

Cryptosporidium is a parasite commonly found in lakes and rivers, particularly those contaminated with animal waste and sewage, and it periodically finds its way into drinking water supplies in large enough amounts to cause serious problems.

Some municipal water utilities, including a number in Southern California, have become more aggressive in recent years in their attempts to head off epidemics by increasing filtering of water and treatment with chemicals. Nevertheless, the organism has emerged as a health threat for the elderly, young children and others with deficient immune systems, including people with HIV, organ transplant patients and those undergoing chemotherapy.

When an outbreak occurs, about 1% of those made ill require hospital care or emergency room treatment, Rose said.

“People with compromised immune systems, especially people living with HIV, need to understand that their public drinking water may not be safe,” said Cornelius Baker, executive director of the National Assn. of People with AIDS, a private advocacy group.

The Centers for Disease Control and Prevention has urged people with AIDS to boil drinking water if they suspect it is contaminated.

Expressing enthusiastic support for the EPA plan, Erik Olson, a senior attorney specializing in water issues at the Natural Resources Defense Council, exclaimed: “It’s a big deal!”

But he said two central questions cannot be answered for some time: Will Congress, concerned about costs and about imposing additional federal regulations, take steps to weaken national standards? And will the government, insisting that the public has a right to know, require utilities to inform users about the extent of the pollution in local supplies?

Two reports prepared last year by the Environmental Working Group and the Natural Resources Defense Council found that water supplies serving 45 million Americans had been tainted by cryptosporidium at some point during the previous two years.

Monthly checks by the Metropolitan Water District, which serves 16 million people in coastal Southern California from Ventura to the Mexican border, have turned up occasional instances of small amounts of cryptosporidium in water supplies, said Rob Hallwachs, a spokesman for the water utility.

“We generally have found minute levels that are far below those in other parts of the country” in the water entering the system from the Colorado River and Northern California sources, he said. “We have none, zero, zilch in the treated water that is distributed” to homes, schools and businesses, he declared.

The microbes are four to six microns in diameter--considerably smaller than the cross-section of a human hair--and are resistant to conventional disinfectants.

The EPA said that current water safety standards are not explicitly designed to ensure removal of the organism because it is so difficult to detect and treat. The monitoring project, and a subsequent effort to draw up a plan to keep it out of water supplies, are intended to overcome this shortcoming.

The study could cost as much as $130 million, including development of plans for remedial action. It will involve water systems serving at least 100,000 people and will be paid for by the water utilities.

Jack Sullivan, deputy executive director of the American Water Works Assn., a 50,000-member organization that represents water utilities across the country, said the eventual cost of protecting the nation’s water supplies is impossible to estimate “because we don’t know . . . the extent of the problem.”